At present, conventional optocouplers are made with a single light emitting diode (LED) and a single photodiode. Typically, the LED and the photodiode are positioned side-by-side and subsequently encased in an optical dome structure that reflects light randomly from the LED to the photodiode. With the present fabrication of conventional optocouplers, optocouplers have several problems or limitations, such as poor performance, i.e., speed, high drive current, large size, and the like.
Since conventional optocouplers having poor performance use an LED, switching speed or the speed of data transmission from the LED to the photodiode is reduced, thus lowering the performance of the optocoupler. Also, since optical coupling of the LED to the photodiode is achieved in a random fashion, optical coupling between the LED and the photodiode is not efficient, thus also lowering the performance of the conventional optocoupler.
Further, with present fabrication techniques and with a large size of the LED and the photodiode, conventional optocouplers are limited to having two LEDs and photodiodes in a single package. Because of this large size, the number of devices in one package is limited and conventional optocouplers are not suitable for high volume applications requiring high volume data transfer, as well as being not suitable for high volume manufacturing. Additionally, since size is prohibitive, conventional optocouplers can not be manufactured to couple a complete word, thus restricting conventional optocouplers to a one or two bit data transfer vehicle.
As can be seen, conventional optocouplers are not capable of present requirements, such as high manufactureability, high performance, and the like. Therefore, an optocoupler structure that is highly manufacturable and provides higher performance would be highly desirable.